I am very religious about cleaning the coils on the inside unit.My central unit kept freezing up when we first moved in this place, when I took off the top cover thing only took a second to see why....the coils were absolutely filthy, but after cleaning them and straightening the fins it works like a new one lol
Did preliminary voltage tests up to, and thru the contactor going to the compressor, all good. On the phone with 'the guy' I told him of the tests I had done and he said: "it's probably the capacitor" and I told him that the top of it looked bowed up, and he said: "Yep! ". He will visit tomorrow morning.
I blame @zannej !